The **Cardiac Index Calculator** helps determine an individual’s cardiac output adjusted for body surface area (BSA). Cardiac index (CI) is a vital measure for assessing cardiac function relative to body size, providing a more personalized evaluation compared to cardiac output alone. By calculating CI, healthcare providers can better understand how well the heart is pumping blood to meet the body’s needs.

## Formula of Cardiac Index Calculator

The formula for calculating the cardiac index (CI) is:

**Cardiac Index (CI) = Cardiac Output (CO) / Body Surface Area (BSA)**

where:

**Cardiac Index (CI)**= Cardiac output adjusted for body surface area, measured in liters per minute per square meter (L/min/m²).**Cardiac Output (CO)**= The total volume of blood pumped by the heart per minute, measured in liters per minute (L/min).**Body Surface Area (BSA)**= The total surface area of the body, measured in square meters (m²).

### Calculating Body Surface Area (BSA)

To calculate BSA, the Du Bois formula is commonly used:

**BSA (m²) = 0.007184 × (Weight (kg) ^ 0.425) × (Height (cm) ^ 0.725)**

where:

**Weight**= Weight of the individual in kilograms (kg).**Height**= Height of the individual in centimeters (cm).

### Final Calculation Steps

**Measure Cardiac Output (CO):**This is typically obtained using medical devices.**Calculate BSA:**Use the Du Bois formula with the individual’s weight and height.**Compute the Cardiac Index (CI):**Divide the cardiac output by the calculated BSA to obtain the cardiac index.

### Common Terms and Quick Reference Table

For ease of understanding and frequent usage, here is a table to assist users with general cardiac terms and values, enabling quicker reference without repeated calculations.

Term | Definition | Units |
---|---|---|

Cardiac Output (CO) | Total blood volume pumped by the heart/minute | Liters/min (L/min) |

Body Surface Area (BSA) | Total body surface calculated using height/weight | Square meters (m²) |

Cardiac Index (CI) | Cardiac output normalized for body surface area | L/min/m² |

Common CI Range | Normal values for healthy individuals | 2.5 to 4.0 L/min/m² |

These values are general reference points; actual values may vary based on the patient’s health, age, and body composition.

## Example of Cardiac Index Calculator

To illustrate the calculation, let’s go through an example:

**Patient Data:**

**Weight:**70 kg**Height:**175 cm**Cardiac Output:**5 L/min

**Step 1:** Calculate BSA using the Du Bois formula:

**BSA = 0.007184 × (70 ^ 0.425) × (175 ^ 0.725)**

This gives a BSA of approximately **1.86 m²**.

**Step 2:** Calculate CI:

**CI = Cardiac Output / BSA**

**CI = 5 / 1.86 ≈ 2.69 L/min/m²**

This CI value of **2.69 L/min/m²** falls within the typical healthy range, suggesting that the patient's cardiac output is likely meeting the body’s demands effectively.

## Most Common FAQs

**What is the normal range for Cardiac Index?**

The normal range for cardiac index in healthy adults is **2.5 to 4.0 L/min/m²**. Values below or above this range may indicate cardiac issues, requiring further medical assessment.

**Why is Cardiac Index important?**

The cardiac index provides a more accurate evaluation of heart function by considering body size, unlike cardiac output alone. This allows for a tailored assessment of whether the heart is pumping sufficient blood for the individual’s needs.

**How is Cardiac Output measured?**

Cardiac output can be measured using medical devices, including echocardiograms, MRI, or catheterization. These devices monitor blood flow to estimate the volume pumped per minute by the heart.